JP3526485B2 - Valve actuator using ultrasonic motor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve actuator using an ultrasonic motor.

[0002]

2. Description of the Related Art FIG. 9 is a schematic view of a manual handle type sluice valve. FIG. 10 is a sectional view of a manual handle type sluice valve.

Various valves are used in pipes for passing gas, water, oil, LPG, LNG, steam and the like. The opening and closing of these valves can be controlled by operating a manual handle screwed onto the valve rod fixed to the valve body in the valve body of the valve, or by installing a control valve actuator, which automatically moves the valve rod. To operate. When operating with a manual handle, there are those in which the manual handle moves up and down together with the valve rod, and those in which the manual handle only rotates but does not move up and down. It is a valve having a structure.

The manual handle type sluice valve 1 shown in FIGS. 9 and 10 moves up and down inside the valve box 2 to flow a fluid (arrow A).
For controlling the valve, a valve rod 4 attached to the valve at a right angle to the flow direction of the fluid, and a male screw rotatably supported by a yoke 5 fixed to the valve box 2 and formed on the valve rod 4. 6
Has a coupling 8, that is, a sleeve 8 having a screw hole 7 having an internal thread portion 7 into which is screwed. A handle wheel 9 is fixed to the sleeve 8. Therefore, the sleeve 8 and the handle wheel 9 integrally rotate on the yoke. By rotating the handle wheel 9 several times to several tens of times, the valve body 3 moves up and down together with the valve rod 4 so that the gate valve 1 is fully opened (shown by a solid line in FIG. 9) or fully closed (shown by a virtual line in FIG. 9). ) To make the fluid flow or stop. The portion where the valve rod 4 projects from the valve box 2 is filled with the gland packing 10 to prevent the fluid from leaking to the outside.

Conventionally, as a valve control actuator, an air motor type, an air cylinder type, an electric motor type, etc. have been used. Air motor type, electric motor type, etc. are often used as actuators such as sluice valves that are most frequently used in piping systems with diameters of several inches or more, but the characteristics required for these actuators are low speed type. It is a high torque type (about several revolutions per minute) (about several tens Nm or more). Further, it is necessary to have a property of preventing a biting phenomenon at the time of opening and closing. For large sluice valves of several tens of inches or more, hydraulic cylinders, hydraulic motors, large air cylinders, special electric motors, etc. are also used as valve actuators. Although not shown, for example, an electric motor type valve actuator connects a gear to the electric motor through a reduction gear, meshes with a gear fixed to the sleeve instead of the handle wheel, and automatically opens and closes the sluice valve by the electric motor. It was done.

[0006]

However, such a conventional valve actuator has the following drawbacks. (1) In the case of a solenoid valve, its driving force is small, so it can be applied only to small diameter piping valves up to about 1 inch,
Further, there is a drawback that it operates only when fully opened or fully closed, and cannot be stopped midway. (2) In the air motor and the air cylinder, expensive instrument air equipment with an air pressure of 7 to 8 kg / which is a drive source is required, and an air solenoid valve for opening / closing control is required. It was difficult to adopt it without the instrument air equipment. Furthermore, since a large amount of air is required for driving, equipment such as a cushion tank was also required in the air piping system from the instrumentation air equipment. (3) The electric motor (1500 to 1000 rpm) requires a high speed reduction type speed reducer of about several hundreds: 1 or more, and complicated torque limit control (commonly known as: to prevent biting at the time of opening and closing). A limit torque mechanism was also required. Furthermore, in order to be able to drive even during a power failure, a dedicated UPS facility or the like that takes into consideration the startup capacity of the electric motor (about 6 times the rated capacity) was required. (4) A hydraulic cylinder or hydraulic motor requires a dedicated hydraulic drive facility and an air solenoid valve for opening / closing control. (5) In cryogenic specifications such as LNG and high temperature specifications such as steam, the gland portion of the valve is long, so in the case of the conventional valve actuator, it may be difficult to apply a large weight to the upper part of the valve and the valve may need to be reinforced ( As will be described later, since the valve actuator of the present invention is lightweight, a large weight does not act on the valve upper part).

The present invention has been made in view of the above points, and is simple and easy to use with a conventional manual handle type valve for piping.
An object of the present invention is to provide a valve actuator that can be easily and inexpensively mounted, can be manufactured into a lightweight and small explosion-proof structure, and has a low speed and high torque performance that is simple and easy to control.

[0008]

In order to achieve the above object, the present invention provides a valve body which moves up and down in a valve box to control the flow of fluid, and a valve body which is perpendicular to the direction of fluid flow. A valve actuator mounted on a sluice valve having a mounted valve rod and a sleeve rotatably supported by the valve box and provided with a threaded portion of the valve rod, on the same axis of the valve actuator. A pinion that meshes with the gear, and an ultrasonic motor paired above and below the pinion and fixed face-to-face with the valve box, the output shaft of the ultrasonic motor being an output shaft of the pinion. It is characterized in that it is engaged with the shaft on the same axis.

Further, the present invention is characterized in that the ultrasonic motor is enclosed in a case having a flameproof structure.

Further, the present invention is characterized in that a plurality of pairs of the ultrasonic motors arranged above and below the pinion are provided around the gear.

Further, the present invention is characterized in that a dedicated driver is attached to each of the ultrasonic motors.

[0012]

[0013]

[0014]

The present invention can be easily applied to all conventional types of manual valves. The ultrasonic motor used has a voltage applied in the ultrasonic range to an elastic body and a stator with a piezoelectric ceramic polarized in the thickness direction so that expansion and contraction alternate when voltage is applied. Since the bending vibration is converted into rotary motion, the load can be driven directly without using a reduction mechanism, etc., and low speed rotation and high torque can be given, making it lightweight, thin, responsive and controllable. Is improved, it serves as a mechanical brake when de-energized, the output shaft can be held, and the rotation noise is quiet,
Since the rotation torque is flat, no bite is generated at the time of fully opening and closing, and the explosion-proof compatibility is improved.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing a schematic structure of a valve actuator according to the present invention. FIG. 2 is a plan view of a main part of the valve actuator according to the present invention. Fig. 3 is the III-
It is a cross-sectional arrow view on the III line.

The valve actuator of the present invention shown in FIGS. 1, 2 and 3 is an improvement of the conventional manual handle type sluice valve 1 described with reference to FIGS. 9 and 10, and instead of the handle wheel 9, a large reduction gear (abbreviated as a gear). It is a modification such as mounting 9A.

In FIGS. 1, 2 and 3, a valve body 3 for vertically moving the inside of the valve box 2 to control the flow of the fluid (arrow A) and a valve body 3 mounted at right angles to the flow direction of the fluid. Valve rod 4
And a coupling 8 or sleeve 8 having a threaded hole, which is rotatably supported by a yoke 5 fixed to the valve box 2 and has an internal thread portion with which an external thread formed on the valve rod 4 is screwed, is provided. ing. A large reduction gear (abbreviated as gear) 9A is fixed to the sleeve 8 on the same axis as the sleeve 8. Therefore, the sleeve 8 and the gear 9A integrally rotate on the yoke 5, and by rotating the gear 9A several times or tens of times, the valve body 3 moves up and down together with the valve rod 4 to fully open the sluice valve 1 or Fully closed to allow fluid to flow or stop. The portion where the valve rod 4 projects from the valve box 2 is filled with the gland packing 10 to prevent the fluid from leaking to the outside. A pinion (small gear) 11 meshing with the gear 9A is arranged on the outer periphery of the gear 9A.

The ultrasonic motors 15 are paired on the upper and lower two stages of the pinion 11 and face each other and are fixed to the yoke 5. The output shafts 16 of the pair of upper and lower ultrasonic motors 15 are connected to both ends of the central axis of the same pinion 11 on the same axis. In the illustrated embodiment, a square hole is formed at the shaft end of the pinion 11, and the corner portion of the tip of the output shaft 16 of the ultrasonic motor 15 is fitted into this square hole. According to the experiment, a pair of upper and lower ultrasonic motors 15 drive about 9 minutes per minute.
A torque of about 1 Newton meter can be generated with 0 rotation.

The ultrasonic motor 15 includes a rotor assembly 15A,
The stator assembly 15B, the large bearing 15C, etc. are enclosed together in, for example, a case 15D having a flameproof structure, and only the tip of the output shaft 16 is projected from the case 15D. The rotor assembly 15A is composed of a slider (thin ceramic ring) and a rotor (aluminum disk), and the stator assembly 15B is made of brass elastic body 15B in the thickness direction so that expansion and contraction alternate when a voltage is applied. It is a bonded piezoelectric ceramic.

4, 5, and 6 are plan views showing another arrangement of the ultrasonic motor in the valve actuator of the present invention.

In the embodiment shown in FIG. 2, six pairs of ultrasonic motors 15 (No.
1-No. 6) It is called a 2-stage 6-set system because it is arranged, but it is a 2-stage 2-set system as shown in FIG. 4, a 2-stage 3-set system as shown in FIG. 5, and a 2-stage 4-set system as shown in FIG. It is possible to appropriately increase the number of groups such as. However, it is important that these sets of ultrasonic motors 15 are arranged in a balanced manner on the outer periphery of the gear 9A so that bending stress does not act on the valve rod 4. In addition, the entire actuator including all the ultrasonic motors 15 is, for example, a case 1 having a flameproof structure.
It is also possible to enclose it in 7. At that time, an appropriate connection spacer 18 is inserted between the case 17 and the ultrasonic motor 15 or between the ultrasonic motors 15.

FIG. 7 is a diagram showing the schematic construction of another embodiment of the ultrasonic motor used in the valve actuator of the present invention.

In FIG. 7, a two-stage ultrasonic motor 25
Are paired in the upper and lower two stages of the pinion 11 and face each other, and are fixed to the yoke 5 (see FIG. 3). The output shaft 16 of the ultrasonic motor 25 is engaged with the shaft of the pinion 11 on the same axis. In the drawing, a square hole is formed in the axis of the pinion 11, and the output shaft 16 of the ultrasonic motor 25 is formed in this square hole.
The tip corners of are fitted. The output shafts 16 of the ultrasonic motors 25 in the upper and lower stages are engaged with the same pinion 11. The ultrasonic motor 25 of FIG. 7 is the ultrasonic motor 15 of FIG.
The difference from is that it has a dedicated driver 24.
The dedicated driver 24 includes an ultrasonic drive circuit and an overcurrent circuit.

The ultrasonic motor 25 is a dedicated driver 24,
The rotor assembly 15A, the stator assembly 15B, the large bearing 15C, and the holding spring and the small bearing 15E are enclosed together in a case 15D having a flameproof structure, and only the tip of the output shaft 16 is projected from the case 15D. The rotor assembly 15A is composed of a slider and a rotor, and the stator assembly 15B is formed by adhering an elastic body and a piezoelectric ceramic polarized in the thickness direction so that expansion and contraction alternate when a voltage is applied. In the above example,
Although the sleeve 8 has been described as the one in which the coupling 8 of the conventional manual handle type sluice valve, that is, the sleeve 8 is used as it is, in order to easily apply the valve actuator of the present invention to various existing piping valves (manual type). Has
It is desirable to make a dedicated simple sleeve that adapts to the shape and size of those valve boxes and the shape and size of the large reduction gear used.

The valve actuator of the present invention having the above structure is drive-controlled as follows.

FIG. 8 is a block diagram of a drive circuit for a valve actuator according to the present invention.

As described above, the embodiment of FIG. 2 is a two-stage six-set system in which six sets (No. 1 to No. 6) of ultrasonic motors 15 are arranged in pairs at the upper and lower stages of the pinion 11. Is. A driving method of this embodiment will be described with reference to FIG. Since the drive circuits of the ultrasonic motors 15 of each set are exactly the same, FIG. 8 representatively shows the drive circuit of the ultrasonic motors 15 of the first set in detail.

The first set of ultrasonic motor Nos. 1 is composed of upper and lower two stages, and the rotors of the upper and lower two stages of ultrasonic motors are fixed to the same output shaft 16, so that the rotation directions are opposite to each other, but the drive circuit has no structure. Is the same. Therefore, the constituent elements of the drive circuit of the upper ultrasonic motor are attached with “a” after the reference numeral, and the constituent elements of the drive circuit of the lower ultrasonic motor are attached with “b” after the reference numeral. Indicate. Also, "F" in the figure indicates the clockwise rotation of the rotor,
"R" means counterclockwise rotation of the rotor.

The drive circuit of the ultrasonic motor includes drive circuits 10a and 10b which receive the F rotation signal or the R rotation signal and generate respective drive signals, and a constant voltage (for example, 5).
V), and oscillators 12a and 12b that receive the output voltages of the regulators 11a and 11b and generate signals of a drive frequency (for example, about 40 KHz), and F that is output from the drive circuits 10a and 10b. Output transformers 13a ₁ , 13a ₂ and 1 for converting the rotation drive signal or the R rotation drive signal into a voltage.
3b ₁ and 13b ₂ , speed setting / control circuits 14a and 14b for setting and controlling the speed of the ultrasonic motor, and overcurrent limit circuits / counters 15a and 15b for preventing overcurrent from flowing to the ultrasonic motor. It consists of and. A DC power source 20 is prepared as a power source for driving the ultrasonic motor.

Now, when the switch SW is connected to the contact a, the F rotation signal is given to the drive circuit 10a of the upper ultrasonic motor, and the drive circuit 10 of the lower ultrasonic motor is supplied.
Since the R rotation signal is applied to b, the drive signals are output respectively, the voltage is converted by the output transformers 13a ₁ and 13b ₂ , and the rotor is supplied with the drive frequency signal generated by the oscillation circuits 12a and 12b. . As a result, the upper ultrasonic motor is rotated clockwise and the lower ultrasonic motor is rotated counterclockwise at the same speed.

Although the description is omitted, other pairs (No. 2 to N)
o. Similarly, the ultrasonic motor 6) is rotated in the same rotation direction as the first set to drive the valve actuator. As a result, the gate valve 1 moves in the opening direction.

When the 6 sets (No. 1 to No. 6) of ultrasonic motors are energized for a certain period of time, the valve actuator is driven and the sluice valve 1 reaches the fully open position. When the flow continues, the illustrated overcurrent limit circuits / counters 15a and 15b operate as follows to stop the rotation of the ultrasonic motor. That is, the overcurrent limit circuits / counters 15a and 15b constantly detect the current I flowing through the rotors of the upper and lower ultrasonic motors, respectively, and when the current I exceeds the overcurrent set value Ir, the oscillation circuit 12a and The oscillation of 12b is stopped for 1 second and the count value of the counter is incremented by 1. If the power is still supplied from the DC power source 20 after 1 second, the oscillation circuits 12a and 12b start the oscillation operation again. As a result, the rotor starts rotating again. As a result, the sluice valve 1 still receives the force to move in the opening direction in the fully open position (however, the sluice valve 1
Does not actually move because it has already reached the fully open position). Therefore, the current of the overcurrent set value Ir or more continues to flow in the rotor of the ultrasonic motor, and the above operation is repeated. That is, the oscillation operation of the oscillation circuits 12a and 12b is stopped for 1 second, the counter counts up, and the oscillation operation starts again. Thus, when the count value of the counter reaches n (for example, 10), the oscillation circuit 12
a and 12b stop the subsequent oscillation operation. As a result, the operation of the valve actuator is stopped, and the opening operation of the gate valve 1 is completed. By doing so, it is possible to prevent unreasonable force from acting on the valve actuator and the sluice valve 1. After that, by moving the switch SW to the c contact, the voltage supply from the DC power source 20 is cut off, whereby the overcurrent limit circuit /
The counters of the counters 15a and 15b are reset.

The operation when the sluice valve 1 is opened has been described above. However, when the sluice valve 1 is closed, the rotation direction of the ultrasonic motor is reversed by connecting the switch SW to the b contact, and the overcurrent limit circuit / counter is operated. The operations of 15a and 15b are exactly the same. The operation of the switch SW when the valve is opened and closed and the switching of the contact of the switch SW by the outputs of the overcurrent limit circuits / counters 15a and 15b can be performed by a controller (not shown) or remote operation.

[0035]

As described above, according to the present invention, the valve body that moves up and down in the valve box to control the flow of the fluid, and the valve rod attached to the valve body at right angles to the fluid flow direction. An actuator mounted on a sluice valve having a sleeve rotatably supported on a valve box and having a threaded portion for screwing the valve rod, wherein a gear fixed to the sleeve on the same axis as the gear and a gear Since the pinion meshes with each other, and the ultrasonic motors that face each other and are paired above and below the pinion and fixed to the valve box face-to-face, the output shaft of the ultrasonic motor is engaged on the same axis as the pinion shaft. An extremely excellent effect can be obtained. (1) The valve actuator of the present invention can be easily attached to a conventional inexpensive sluice valve having a handle specification, and there is almost no need to modify the valve body due to valve automation. That is, only the valve actuator of the present invention is fixed in place of the conventional handle. (2) By adjusting the number of ultrasonic motors to be used, it can be applied to a generally used handle type gate valve for piping having a diameter of about 2 to 12 inches. (3) It is easy to manufacture in a pressure and explosion proof type, can be manufactured in a light weight, and is widely applicable. In particular,
Conventionally, in the cryogenic specifications such as LNG and the high-pitched specifications such as steam, the gland portion of the valve is long and it is difficult to apply a large weight to the upper portion of the valve. However, in the present invention, it is easy to automate because it is lightweight. (4) Since the characteristic that the rotary torque peculiar to the ultrasonic motor is flat can be utilized, a bite prevention mechanism (limit torque) at the time of fully opening and fully closing is not required, and simple control is possible. (5) Even if the valve is fully opened or fully closed, even if a command to close or open the ultrasonic motor is input, the valve is not jammed and is automatically fully opened or fully closed. (6) "Perform" during opening and closing of the valve due to deterioration of the valve over time
Even if there is a position (which requires a large torque), the operation can be continued by repeating inching several times (a slight play of the gear can be injured, and the "make" position can be exceeded).

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a schematic configuration of a valve actuator according to the present invention.

FIG. 2 is a plan view of a main part of a valve actuator according to the present invention.

3 is a cross-sectional view taken along the line III-III of FIG.

FIG. 4 is a plan view showing another arrangement of ultrasonic motors in the valve actuator of the present invention.

FIG. 5 is a plan view showing another arrangement of the ultrasonic motor in the valve actuator of the present invention.

FIG. 6 is a plan view showing another arrangement of the ultrasonic motor in the valve actuator of the present invention.

FIG. 7 is a diagram showing a schematic configuration of another embodiment of the ultrasonic motor used in the valve actuator of the present invention.

FIG. 8 is a block diagram of a drive circuit of the valve actuator of the present invention.

FIG. 9 is a schematic view of a manual handle type sluice valve.

FIG. 10 is a cross-sectional view of a manual handle type (external screw type) gate valve.

[Explanation of symbols]

1 Gate Valve 2 Valve Box 3 Valve Body 4 Valve Bar 5 Yoke 6 Male Screw 7 Screw Hole 8 Sleeve or Coupling 9 Handle Wheel 9A Gear 10 Ground Packing 10a Drive Circuit 10b Drive Circuit 11 Pinion 11a Regulator 11b Regulator 12a Oscillation Circuit 12b Oscillation Circuit 13a ₁ output transformer 13a ₂ output transformer 13b ₁ output transformer 13b ₂ output transformer 14a speed setting / control circuit 14b speed setting / control circuit 15 ultrasonic motor 15A rotor assembly (slider and rotor) 15B stator assembly (brass elastic body) 15C Bearing bearing (large bearing) 15D Case 15E Pressure spring (holding spring) and small bearing 15a Overcurrent limit circuit / counter 15b Overcurrent limit circuit / counter 16 Output shaft 17 case 18 connecting the spacers 20 DC power supply 24 special screwdriver 25 ultrasonic motor SW switch

Continuation of the front page (56) Reference JP-A-3-96776 (JP, A) JP-A-7-301355 (JP, A) Actually open 5-57672 (JP, U) Actually open 59-22377 (JP , U) Patent 3209391 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16K 31/00-31/05

Claims (4)

(57) [Claims] 1. A valve body for controlling a fluid flow by moving up and down in a valve box, a valve rod attached to the valve body at a right angle to a fluid flow direction, and rotatably supported by the valve box. In a valve actuator mounted on a sluice valve having a sleeve having a threaded portion of the valve rod, a gear fixed to the sleeve on the same axis as the gear, a pinion meshing with the gear, and the pinion. A pair of ultrasonic motors, which are fixed face-to-face with the valve box in a pair above and below, and the output shaft of the ultrasonic motor is engaged with the shaft of the pinion on the same axis. Valve actuator using ultrasonic motor. 2. The valve actuator using the ultrasonic motor according to claim 1, wherein the ultrasonic motor is enclosed in a case having a flameproof structure. 3. A valve using an ultrasonic motor according to claim 1, wherein a plurality of pairs of the ultrasonic motors arranged in pairs above and below the pinion are provided around the gear. Actuator. 4. The valve actuator using the ultrasonic motor according to claim 1, wherein a dedicated driver is attached to each of the ultrasonic motors.